An inkjet head, more generally referred to as a liquid discharge head, used in a printer or other liquid discharge apparatus has a head with a piezoelectric element for discharging ink, or other liquids, and a driving control integrated circuit (IC) for driving the piezoelectric element. A substrate, on which the driving control IC is mounted, or a substrate, on which an electronic component is mounted, is generally accommodated within an inner cover to prevent adhesion of ink or foreign matters to the substrate.
Heat generated by the driving control IC is transferred to the outside by the inner cover functioning as a heat sink. Thus, as the inner cover becomes physically larger, it dissipates more heat generated by the driving control IC. In recent years, the load of the driving control IC has been increasing due to increases in printing rates/speeds, and this has led to an increase in the amount of heat generated by the driving control IC. Considering overall limits on the acceptable size of the entire apparatus, the continued enlargement of the inner cover size to account for increases in heat generation has reached its limit.